Help with reducing the number of drives in an array configuration

[Talos]

Hello,

 

Recently i had two drives in my array show up as failing SMART due to Seek Error Rate thresholds exceeded. They've since stopped showing this but i dont trust those drives now and I'd been planning on changing up my array anyway so I bought 4x16tb drives to replace those two and some others in my array.

 

My current configuration is:

Parity - 18TB

Disk 1 - 8TB

Disk 2 - 6TB - This is one of the dying drives

Disk 3 - 6TB - This is the other dying drive

Disk 4 - 3TB

Disk 5 - 3TB

Disk 6 - 3TB

Disk 7 - 6TB

Disk 8 - 8TB

Disk 9 - 18TB

Disk 10 - 6TB

 

I want to remove the two drives that showed the SMART errors, and consolidate the 3tb drives and 6tb drives to single 16tb drives, shrinking my array configuration down to 8 drives from 11 and end up with the following configuration:

Parity - 18TB

Disk 1 - 16TB

Disk 2 - 16TB

Disk 3 - 16TB

Disk 4 - 16TB

Disk 5 - 8TB

Disk 6 - 8TB

Disk 7 - 18TB

 

I'm hoping someone can suggest the best method to do this. I've only ever expanded my array by adding more or larger drives over the past 15 years, I've never actually shrunk the number of drives used in the array. My end goal is to end up with a smaller case and less power hungry setup to try and save on some electricity running costs as well as claim back some desk space. 

 

I've already pre-cleared the 4x16tb drives and they are all sweet.

 

Any guidance would be greatly appreciated.

Cheers,

[itimpi]

It depends on whether you are prepared to take any risks with the current data.

 

The simplest and probably quickest way would be to use the New Config tool and via that assign the disks that you want to finish up with removing the surplus drives; start the array;  format the new disks;  and then build parity based on those.    You could then mount each of the drives removed in turn via Unassigned Devices and copy their data back to the array.   This has the risk, though, of one of the removed drives failing before you can copy their data back to the array (thus losing the contents).

 

Any other approach is going to be more laborious but it should be possible to keep parity protection in place so you are protected against a single drive failure, but it will take longer and put more overall stress on the drives.

[Talos]

21 minutes ago, itimpi said:

It depends on whether you are prepared to take any risks with the current data.

 

The simplest and probably quickest way would be to use the New Config tool and via that assign the disks that you want to finish up with removing the surplus drives; start the array;  format the new disks;  and then build parity based on those.    You could then mount each of the drives removed in turn via Unassigned Devices and copy their data back to the array.   This has the risk, though, of one of the removed drives failing before you can copy their data back to the array (thus losing the contents).

 

Any other approach is going to be more laborious but it should be possible to keep parity protection in place so you are protected against a single drive failure, but it will take longer and put more overall stress on the drives.

Yeah that was my concern. With two drives showing the seek errors and only being able to replace them one at a time and still keep the array parity protected I'm not sure the other drive would survive a parity rebuild...

 

I was thinking i would have to do the break the array and restart parity and then copy the info from the removed drives as you said via unassigned devices. The data that is on those two erroring drives is just movies/tv shows which I've made a full listing of so worst case scenario i can just reacquire it if the drive dies completely in the middle of the process.

 

So by doing a "New Config" it will not erase any of the existing disks in my array and allow me to rebuild a new parity based on the new drives Ive inserted plus those I'm keeping from the existing array?

[itimpi]

The New Config tool is covered here in the the online documentation accessible via the ‘Manual’ link at the bottom of the GUI or the DOCS link at the top of each forum page.